From BlenderWiki

Blender 2.65 Release Notes

The Blender Foundation and online developer community is proud to present Blender 2.65. We focused on making this the most stable release in the 2.6 cycle yet, fixing over 200 bugs.

Fire simulation was added along with many improvements in smoke simulation. In Cycles, motion blur, open shading language and anisotropic shading support was added. For mesh modeling, the bevel tool was much improved, a new symmetrize mesh tool was added, and new Laplacian smooth, decimate, and triangulate modifiers are available.

Fire simulation was added to the Smoke Simulator. The domain received major updates to improve performance and usability. Smoke can be emitted from mesh surfaces, without the need for a particle system. A smoke flow force field was added to improve interaction with other simulations. Colored smoke simulation and mixing is possible and the interaction of smoke with collision objects has been improved.

Support for writing custom shaders in the Open Shading Language is now available. Motion blur rendering was also added, to make moving objects and cameras appear blurry. There is also an anisotropic shading node, and BSDF nodes can now have different normals, which can be set using the new bump and normal map nodes. Border rendering in the viewport now also works outside of the camera view.

The bevel tool now includes rounding and was otherwise much improved, preserving the requested bevel width more evenly and generating better topology. A new symmetrize tool was added to make mesh topology and data symmetric.

The decimator was rewritten, and now preserves UV's and vertex colors, has an un-subdivide and a mode to dissolve vertices to create planar n-gons. A new laplacian smooth modifier can reduce noise or smooth the mesh while preserving edges and volume. A triangulate modifier was also added, which can be useful for creating game assets with baked normal maps.

New features include: a tool transfer vertex weights from one mesh to another, antialiased viewport drawing, connected proportional editing in UV editor, improved DPX file read and write, more control over curve taper, collision masks in the game engine and improved camera title safe drawing.